Field of Invention
The present invention relates generally to use of multiple external sensor transceivers with a sensor. Specifically, the present invention relates to determining whether an external sensor transceiver is a new external sensor transceiver and, if so, conveying stored measurement information to the new external sensor transceiver.
Discussion of the Background
A sensor may be implanted within a living animal (e.g., a human) used to measure the concentration of an analyte (e.g., glucose or oxygen) in a medium (e.g., interstitial fluid (ISF) or blood) within the living animal. The sensor may include a light source (e.g., a light-emitting diode (LED) or other light emitting element), indicator molecules, and a photodetector (e.g., a photodiode, phototransistor, photoresistor or other photosensitive element). Examples of implantable sensors employing indicator molecules to measure the concentration of an analyte are described in U.S. Pat. Nos. 5,517,313 and 5,512,246, which are incorporated herein by reference in their entirety.
Data transfer occurs between an implanted sensor and an external sensor transceiver only when the external sensor transceiver is in the proximity of the implanted sensor. Different external sensor transceivers may be used to obtain analyte measurement information from an implanted sensor (e.g., if an external sensor transceiver stops working or a patient changes doctors). When more than one external sensor transceiver is used to obtain analyte information from an implanted sensor, measurement information may be lost (e.g., previous analyte measurement readings). However, the implanted sensor has no way of detecting when the external sensor transceiver has changed.
There is presently a need in the art for a sensor capable of being used with multiple external sensor transceivers while reducing and/or eliminating loss of measurement information and/or calibration parameters.